US603038A - Field - Google Patents

Description

(No Model.)

W. H. HARFIELD.

STEAM STEERING GEAR.

No. 603,038. Patented Apr. 26, 1898.

Inventor? m wd I w I 4 UNITED STATES PATENT rrion.

STEAM STEERING-G EAR.

SPECIFICATION forming part of Letters Patent No. Application filed October 29', 1897.- $erial No. 656 798. (No

603,038, dated April 26, 1898. model.) Patented in England March 22, 1889,1Io. 5,018.

To all whom it may concern:

Be it known that 1, WILLIAM HORATIO HAR- FIELD, a subject of the Queen of Great Britain, residing at London, England, have invented new and useful Improvements in Steam Steering-Gear, (for which I have obtained a patent in Great Britain, No. 5,018, dated March 22, 1889,) of which the following is a specification.

My invention relates to improvements in actuating the valve-gear of engines used for steering ships, and more particularly applies to that kind of gear where the direction of motion of the said engines is changed or revcrsedby an auxiliary valve which transposes alternately the pressure and exhaust sides of the ordinary slide valves. This auxiliary valve (usually termed a reversing-valve, but which also acts as a starting and stop valve) has to be controlled by the steersman, so that the engines will follow concurrently the motions of the steering-wheel. Now in order to eiiect this concurrent motion more eliiciently than hitherto I connect to the rod actuating the reversing-valve a small wormwheel which has two worms or screws gearing into it, one on either side. One of these worms is in connection with and turned by a shaft driven by the engine. The other worm is in connection with and turned by the steering-wheel. It now the steering-wheel be turned, then the worm connected with it revolves the worm-wheel, rolling it along the other worm, as upon a rack, and causes the valve-rod to be moved, thereby opening the valve and starting the engine, which immediately revolves the other worm and (as I so arrange it) draws or works back the wormwheel in the contrary direction, tending to close the valve.

To enable my invention to be fully understood, I will describe the same with reference to the accompanying drawing, which is a plan, partly in section, of a steering-engine rovided with my improvements.

at a are the engine-cylinders, each of which is provided with a piston b and with a valvechest 0, containing a slide-valve d, and e is the crank-shaft, all of which parts are of ordinary construction and form no part of my invention.

f is the auxiliary or reversing valve, which,

as shown, is of cylindrical form. This valve is located in a chamber g between the valve chests c c and is supplied with steam from the boiler through the orifices h h.

'11 t j j are two pairs of passages for establishing communication between the chamber g and the valve-chests c c, which passages are so placed that they can be opened or closed simultaneously by the valve f and that they will lead to the outer and inner sides of the valves d (L, respectively. The valvef' is shown in the mid or closed position; but either the passages i or 3' can be opened by moving the valve to the right or left hand. hen one set. of passages-say i 'iis open, steam will pass to the engine slide-valves, while the other set of passages j 3' will serve for the return or exhaust, and vice versa, when the passages j j are opened.

The rod 10 of the valve f is connected to a bar Z, which carries upon a pin or stud m a small worm-wheel a. With this wheel a, but upon opposite sides thereof, gear two screws or worms 0 p, which are parallel with each other and carried in two cross-pieces q q, mounted upon the bedplate of the engine and serving as a guide or support for the bar Z. The worm o is geared with the crank-shaft e of the engine through the medium of the worm-wheel 'r and the worm .9, while the worm p is rotated by the steering-wheel t, which may be placed in any position in the ship and connected with the said worm by shafting.

The operation of my improved apparatus is as follows: Suppose that the steering-wheel t is turned in the direction indicated by the arrows 1 1. The worm p then acts upon the wheel it, turning it upon its stud and rolling it along the other worm 0, thus drawing the bar Z and valve f forward or toward the right. This at-once opens the passages 'i i, so that steam is admitted to the valve-chests and cylinders and the engine starts. The worm s and worm-wheel 'r then rotate the worm o in the direction shown by the arrow 2, this direction being contrary to and counteracting that of the worm 19, thereby tending to move the valve f back again to close the ports and stop the engine, which it will do should the steersman cease to move the wheel 15. The engine will always work concurrently with all the steersmans movements that is to say, it will run fast when the wheel t is moved I ing-shaft, of a valve-chamber provided with quickly and slowly if the wheel is moved slowly, because the engine works back the valve f until the rates of motion of the worms oandp correspond. Forinstance, should the worm 19 move faster than the worm a worm engaging said worm-wheel, and a worm-shaft operated by the engine-shaft provided with a worm engaging said worm-wheel for moving said valve back to its normal position, described.

2. In a steam steering-gear, the combination with the engine-cylinder, of a controlling efor, a valve-rod con- Again, opposite direction to that indicated by the arrows then the valve f quiclrly closes the valve back into its initial position, substantially as described.

In a steam steering-gear, the combination with the engine-cylinder, piston and driving-shaft,of a controlling and reversing valve, a longitudinally-movable bar connected to said valve, said bar being mounted in stationary guides, and provided with a worm-wheel, a worm engaging said worm-Wheel 011 one both worms in one direction, the passagesjj to the steam, the passages i '5 serving for the exhaust. The engine then commences running in the contrary direction to that previously described, and it will act in the reverse manner in accordance With the movements of the steering-wheel.

I have described my improvements as applied to engines operated by steam, it is to be understood that they are side, and operatively connected'wit-hthe also applicable to engines operated by air, steering-wheel, and a Worm engaging said water, or other fluid pressure. worm-wheel on the opposite side and opera- Having now particularly described and astively connected with the engine, substancertained the nature of my said invention and tially as described. in what manner the same is to be perfol med WILLIAM. HORATIO HARFIELD. I declare that what I claim is- Witnesses:

1. In a steam steering-gear, the combina- W. F. DUNTON, tion with the engine-cylinder, piston and driv- W. DOREY.

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